Know Your Numbers

Diagnostic Criteria for Diabetes

The American Diabetes Association recommends that all adults over 45 years of age be tested for type 2 diabetes. Adults younger than 45 years should get tested if they are overweight or obese and have one or more additional risk factors.

There are three types of tests to diagnose type 2 diabetes:

Hemoglobin A1C

A test for hemoglobin A1C, also known as HbA1C or just A1C, measures the percent of hemoglobin in the blood that is glycosolated. This process occurs when blood is exposed to glucose in the blood stream. The greater the percentage of hemoglobin A1C, the greater the average plasma glucose concentration over the previous months. An A1C measure of ≥ 6.5% would be considered diabetes.

Fasting Plasma Glucose

Following an 8 to 12 hour fast, a simple blood test can determine the level of plasma glucose. A measure of ≥ 126 mg/dL is diagnostic of diabetes.

Oral Glucose Tolerance Test (OGTT)

Two hours after swallowing a sweet liquid, a blood test is performed to determine how quickly the glucose is cleared from the blood. A measure of ≥ 200 mg/dL is diagnostic of diabetes.

Numbers to Know if You Have Diabetes

When you have diabetes, controlling cholesterol and blood pressure are just as important as keeping your blood glucose in check. Cardiovascular disease is the leading cause of death among people with diabetes.

If you have diabetes, you can take steps to lower your risk of heart attack or stroke by reducing your A1C to less than 7%, lowering your blood pressure to less than 130/80 mmHg, and aiming for the following blood lipid numbers:

  • LDL cholesterol less than 100 mg/dL
  • HDL above 40 mg/dL for men and above 50 mg/dL for women
  • Triglycerides below 150 mg/dL

You can also ask your health care provider about taking aspirin. If you smoke, get help to quit by calling the Tobacco Quitline at 1-800-784-8669.